Soap manufacture



INVENTOR /Marf/h [ff/Jeri M. H. ITTNER SOAP MANUFACTURE Original Filed Aug. 2, 1940 March 21, 1950 Patented Mar. 21 1950 UNITED STATES PATENT OFFICE SOAP MANUFACTURE Continuation of application Serial No. 349,914, August 2, 1940. This application November 2, 1944, Serial No. 561,586

9 Claims.

The present invention provides new and useful methods for the manufacture of a variety of useful soap products through the intermediary of molten anhydrous soap, and particularly with the use of molten anhydrous soap which has been largely freed from glycerine and volatile impurities while in a molten state.

In one of my prior inventions for making soap and glycerine, U. S. Patent No. 1,918,603, issued July 18, 1933, I called attention to the fact that the anhydrous soap thus produced might be brought into usable condition by a number of different methods, and I pointed out that, regardless of the method employed to make a usable product, it was practically essential to exclude air or other oxidizing influences from the molten anhydrous soap at the high temperature necessary to melt it, or until the soap had been mixed with other material, and until it had been substantially reduced in temperature. A method of preparing the molten anhydrous soap, which I have employed, is to run the molten soap onto cooled surfaces in such a manner that air is substantially excluded from the hot molten anhydrous soap. Such soap may be dispensed for use in anhydrous condition or may be hydrated.

Perhaps the most useful form of soap in a condition preliminary to conversion into many salable forms of toilet and household soap is a hydrated soap with a controlled degree of hydration, either pure or mixed with suitable soapbuilding materials such as sodic carbonate, sodic silicate, sodic phosphate, sodic pyrophosphate and the like. A soap of this kind is solid at most ordinary temperatures but may be melted readily at temperatures well below the atmospheric boiling point of water. A way I have found to prepare soap in this form from molten anhydrous soap prepared by my former process, or in any other manner, as by heating fatty materials and alkaline or basic material together in tubes, is to run the molten anhydrous soap into water or to run Water onto the molten soap with which it mixes readily giving hydrated soap with varying degrees of water content.

Molten anhydrous soap, suitable for use in this process, may be made according to the method disclosed in my United States Patent No. 1,918,- 603. Fat or fatty oil is saponified in a closed vessel by the use of a sufiicient quantity of basic or alkaline material to convert all or substantially all of the fat or oil into soap. The soap is agitated by a current of steam to ensure complete saponification and to prevent local overheating at the temperatures to which the soap is subjected in order that it may be maintained in a molten, anhydrous condition. While the soap is in the molten, anhydrous condition, exposure to air or oxidizing media must be prevented.

The current of steam not only serves to thoroughly agitate the soap and thus prevent local overheating, but it also aids in volatilizing and removing glycerine, water, and other volatile impurities from the mass of soap. Removal of these volatile impurities from the soap may be facilitated by the aid of diminished pressures in the still or vessel. The glycerine and water vapor may be condensed together or almost completely separated from one another by fractional condensation,

The conditions described in my process and which are more fully set out in my Patent No. 1,918,603 are also effective in removing unsaponifiable volatile impurities from the soap.

The present invention provides a method of handling or treating anhydrous soap by utilizing the molten anhydrous soap in the still or evaporating chamber. It is apparent that the anhydrous soap which is to be treated according to the process of this invention may be obtained by any method; however, the method of my prior patent is a desirable and preferred source of supply for the molten anhydrous soap of this invention.

In mixing molten anhydrous soap and water, regardless of the means of mixing employed, it is important that, at and immediately following the moment of mixing, the degree of mixing shall be most thorough as otherwise a portion of the anhydrous soap, the melting point of which is commonly very high and may even exceed 300 0., is apt to become solidified and thus interfere with the operation of the process and the homogeneity of the product, necessitating powerful disintegrating and powerful mixing machinery to give even a semblance of homogeneity.

Although I have used many methods of mixing molten anhydrous soap and water with the substantial exclusion of air and oxidizing influences, I have found that it is somewhat easier to mix water, or aqueous solutions of soap building ma terials, with a molten hydrated soap having a comparatively low melting point well below the atmospheric boiling point of Water, than it is to mix water or aqueous solutions with molten anhydrous soap with a chilling point that may even exceed 300 C. I have also found that it is easier to mix to homogeneity, molten anhydrous soap with molten hydrated soap than it is to obtain homogeneity with the addition of water alone to the molten anhydrous soap, although I have also made hydrated soaps successfully by mixing molten anhydrous soap with water alone.

I have thus found that a very simple, efiicient, and economical method of converting molten anhydrous soap into a good salable useiul prod not is to mix it intimately with a desired proportion of molten hydrated soap which may be a pure soap or may have incorporated in it any desired amount of materials such as are commonly incorporated in soap, as for instance sodium carbonate, sodium silicate, sodium phosphate of any variety, borax, synthetic detergents whether sulphates, or sulphonates, or phosphates, or borates, or the like. The proportions of molten anhydrous soap and of hydrated'soap, one to the other, that may be employed may vary advantageously over a wide range according to the final product one wishes to obtain. Also, the

degree of hydration maintained in the molten 2 hydrated soap used for mixing with the molten anhydrous soap may vary over a considerable range, it being only necessary to maintain the molten hydrated soap in a sufiiciently free flowing state so that it can be run or be forced through conduits or directed channels, and so that it will lend itself freely to mixing operations.

I find that certain solutions of soap builders as sodium si1icate,.sodium carbonate, sodium phosphates and the like whether these be entirely dissolved or partially in suspension in these solutions, mix readily and evenly with molten anhydrous soap in my process'to make-soaps containing desired proportions of the builders taken, with more or less or no moisture in the finished product, as desired, and as may be controlled by amount of moisture in the. solutions employed, and by various physical conditions employed, as temperature, pressure, and moisture control conditions known to the art.

While my process is not confined, for its successful operation, to any'given type of apparatus but may be carried out with a variety of apparatus, I have found that certain kinds of apparatus illustrated in the drawings are eminently u suited thereto.

While I prefer to operate on anhydrous soaps at temperatures at which they are distinctly molten it is nevertheless within the scope of the invention to employ also plastic and semiplastic anhydrous soaps which are at a sufficiently high temperature or which have a requisite degree of fluidity so they will flow in, conduits either by gravity alone or with the aid of an impelling force.

The'following examples are given merely for illustration of some of the applications of the invention and are not to be interpreted as limiting the scope of the invention in any way.

Example I Molten anhydrous soap at a temperature of about 300 C. and molten hydrated soap containing about 30% water and at a temperature of about 100 C. are flowed'continuously at a sub-- stantially uniform relative rate of 100 lbs. of the former to about 80.3 lbs. of the latter so that the two streams of liquid soap will enter into intimate confluence, and mixing, the intimacy of the mixing being further promoted by mechanical means. During the mixing the excess heat of the molten anhydrous soap will be absorbed in converting water from the molten hydrated soap into steam. During this part of the process the entire soap mixture will have become partially dried by this conversion of water into steam and will have become comminuted into solidifying granules which will be expelled from the mixer with the aid of mechanical means, promoted largely by the outward rush of steam formed by drying moisture out of the molten hydrated soap, and will issue in solid spray form. At the instant of expelling the granulated soap and steam into the surrounding gaseous or vapor envelope the pressure around the granules will drop practically instantly, effecting the simultaneous release. of the rest of the water remaining in the granules, as steam, resulting in a three-fold action on the granules of expanding them, cooling them to the temperature of the surrounding gaseous or vapor envelope, and leaving them in solid substantially anhydrous condition ready for use as a detergent, and for other uses.

Example II A very desirable form of soap, as for example soap for manufacturing into floating soap, is a hydrated soap of suitable composition containing about 30% water. Such a soap may be made very advantageously from molten anhydrous soap in the following manner. Molten anhydrous soap, of suitable composition, at" a temperature of about 300 C., is mixed intimately and substantially continuously with a molten hydrated soap with substantially the same composition, and having a temperature of about 100 C., the hydrated soap having a somewhat higher water content than that of the finished soap that is to result from the process. The'excess heat of the molten anhydrous soap above about 100 C. is absorbed byconverting some of the water'of the molten hydrated soap into steam at about 100 C. The intimately mixed soaps may be dis charged beneath the surface of a body of molten hydrated soap and the excess steam allowed to escape or it may be collected by means of a suitable contrivance, for use. A considerable amount of the molten hydrated soap is recirculated for mixing with fresh molten anhydrous soap, and the amount of soap thus recirculated need not be fixed though it is desirable that it shall be considerable. Before bringing the recirculated molten hydrated soap into confluence with the molten anhydrous soapa stream of boiling water may be injected by suitablemeans into the recirculating molten hydrated soap thus increasing temporarily its water contentto somewhat above 30%. By maintaining substantially uniform relative rates of flow of the several moving fluids, and by regulating the amount of boiling Water injected into the'fast moving stream of recirculatin molten hydrated soap so that about 24 lbs. of water will be'thus'used for each 100 lbs. molten anhydrous soap taken, theresult' will be that all of the anhydrous soap will have become converted into'a molten hydrated soap at a temperature of about 100 C. having about 30% water content.

Eficample III Forpreparing a soap in granular. form suitable for use in hard water'a molten anhydrous soap at a temperature of about 300? 0., made from tallow and coconut oil in theproportion of. about two of the-former tonne of the latter-may be mixed in the manner disclosed-with a mixture at a temperature of about'l00 C., comprising about 38% sodium silicate, for each 100 lbs. of the above molten anhydrous soap taken. The above solution mixture and the molten anhydrous soap may be mixed together at uniform rates in the proportions given above and the intimacy of the final mixture may be assured by regular confluent flow augmented by efiicient mechanical means. The mixture thus formed is discharged as a spray into an open or closed drying tower suitable for spray drying and having controlled drying conditions with the result that for each 100 lbs. of molten anhydrous soap taken there will be formed 125 lbs. of a solid granular soap product ready for packaging and having a composition of- 80% anhydrous soap silicate of soda (anhydrous) 5% sodium carbonate 5% moisture while at the same time there will escape from the tower about 2'7 .9 lbs. of water vapor. In order to prevent the re-absorption of moisture by the granular soap product, it is only necessary to maintain its temperature slightly above the saturation temperature of water vapor at the pressure employed until the product is removed from contact with excess water vapor.

Example IV A soap suitable for conversion into toilet soap may be made from a mixture comprising about 20% refined coconut oil and about 80% prime tallow. A molten anhydrous soap having a composition as indicated above and at a temperature of about 300 C. is intimately mixed in the manner disclosed with a molten hydrated soap of similar composition but having a water content of about 80% and a temperature of about 100 C. The molten hydrated soap may be prepared after the manner illustrated in Example II or other- .wise. For each 100 lbs. of the above molten anhydrous soap taken, there is taken and simultaneously mixed therewith about 184 lbs. of the above described molten hydrated soap, and there results a comminuted sprayed product comprising about 260.2 lbs. and having a moisture content of about 12%, and being in a condition suitable for immediately milling and plodding into toilet soap after amalgamation of suitable perfume therewith. The water content may be lessened, if desired, where a larger proportion of perfume material is employed, or a higher percentage of moisture may be left in the finished soap, if desired.

The conditions used in the process illustrated by the examples and the water content of the finished products may be varied without substantially affecting the principles involved.

The process of the invention is not limited to any single type of apparatus but may be carried out in a considerable variety of apparatus. While I picture and describe apparatus suitable for carrying out the invention, it will be understood that other apparatus may be used.

Fig. 1 is a diagrammatic view of a suitable mixer located partly immersed under the liquid level in a soap tank.

Fig. 2 is a diagrammatic view of a soap mixer and spraying apparatus suitable for producing a dry or dried product in subdivided form.

Fig. 3 is a detail of a moving part of the apparatus shown in Figs. 1 and 2.

Referring particularly to Fig. l, a double jacketed pipe 2 is provided with a central space I through which molten anhydrous soap may flow, or plastic or semi-plastic anhydrous soap may be forced from a suitable vessel, not shown, in which it is made. Around the double walled heat-insulating pipe 2 there is a space 3 confined by an outer, larger pipe with one end flaring outwardly surrounding chamber l4. Pipe 4 connects with space 3 and permits of the flow of water or other liquid therethrough to space 3. Liquid may enter pipe 4 and space 3 either through valve 5 or through valve l8. Liquid flowing through space 3 comes into contact in chamber M with liquid flowing through space I where the two become mixed by direct contact and are diverted in mixed condition by cone [3 attached to rapidly revolving impeller 6 shown in some detail in Fig. 3. The mixed liquids become very intimately mixed by the action of impeller 6 from which the resulting mixture is thrown off with great force. Impeller 6 has open spaces l6 between vanes l5 and revolves so that the convex side of the vanes moves forward. Impeller B is attached to shaft 1 driven by suitable means as for example motor 8, or otherwise.

The apparatus illustrated in Fig. 1 may be employed for making a variety of hydrated products by the invention. Water or water-containing liquid may be run through valve 5 and pipe 4 to space 3 and chamber M where it comes into contact with hot molten anhydrous soap entering through space I, and the two become intimately mixed in chamber [4 by flow and by impeller 6 and are discharged into tank 9. A considerable amount of steam will be generated by the heat of the molten anhydrous soap on the water in chamber l4 and the resulting soap will be cooled thereby. Tank 9 may be filled in this way up to the overflow pipe and valve l2 with molten hydrated soap. A suitable stuffing box It] may be provided around shaft 1. The molten hydrated soap thus formed may be conducted away through valve [2 or valve 1 l, or a portion of it may be recirculated through valve I l and a pump, not shown, through valve l8 and pipe 4 where water or water-containing liquid may be added in desired amounts through valve 5.

The apparatus of Fig. 2 may be employed to make dry, or dried products by spraying. Molten anhydrous soap may be conducted through space I to chamber l4 where it will meet water or molten hydrated soap or water-containing liquids entering through valve 18 and pipe 4 which, in this case, also may be supplied with a branch line, and valve 5, as shown in Fig. 1. In the operation of the apparatus of Fig. 2 it is generally desirable to use relatively more of the molten anhydrous soap and less water or molten hydrated soap or other water-containing liquids, so as to give a dry or dryer product. The hydrated product entering through pipe 4 should supply sufficient water to be evaporated as steam by the excess heat in the molten anhydrous soap to cool the mixture to at least about the atmospheric boiling point of water, and when a hydrated product is desired some excess water should be supplied through pipe 4. The product formed, and ejected from chamber [4, will be ejected with the aid of the revolving impeller 6 and also very considerably by the outrush of steam that is formed in the mixing.

With a proper proportioning of molten anhydrous soap and water-containing liquid taken, it is possible to make a wide variety of spray prodnets in the apparatus of Fig. 2 which may range from pure sprayed anhydrous soap to dry or the dew point, the steam formed in chamber I i and escaping into tower l1 will'no-t condense to any serious degree on theproduct. Tank I? may be any suitable type of spray-tower, covered or uncovered.

The present application is a continuation of my prior co-pending application Serial No.

349,914, filed August 2, 1940 (now abandoned).

As many widely different embodiments of the present invention may be made without departing from the spirit or scope thereof, itis not tobe i limited except as defined in the following. claims.

I claim: 1. An apparatus for producing soap of a desired moisture content which comprises means adapted 'to contain a soap mass, means for discharging a stream of soap into said soap mass througha pipe whose outlet is surrounded by said soap mass, means for removing vapors from said first named means, means for supplying water to said first named means, means for withdrawing material from said soap mass, and means for vaporizing water from the material thus removed to produce a soap of desired moisture content.

2. The method of producing a solid soap from molten anhydrous soap which comprises bringing '1.

molten anhydrous soapinto contact with watercontaining liquid in a mixing chamber, substantially immediately subjecting the same to intense mechanically induced mixing, expelling the mixture from said chamber with the aid of steam generated in said chamber, and solidifying the expelled soap.

3. The method of producing a solid soap from molten anhydrous soap which comprises bringing molten anhydrous soap into contact with watercontaining liquid in a mixing chamber, substantially immediately subjecting the same to intense mechanically induced mixing, expelling the mixture from said chamber into a tower in the form of granules with the aid of steam generated in said chamber, and solidifying the granules in the tower.

4. The method of producing a-solid soap from molten anhydrous soap which comprises bringing molten anhydrous soap into contact with water soap from molten anhydrous soap which comprises bringing molten anhydrous soap into contact with a liquid containing water and a builder,

substantially immediately subjecting the same to intense mechanically induced mixing, expelling the mixture .in the form of granules from said chamber into a'tower with the aid of steam generated in said chamber, and converting said granulesto solid soap particles with the aid of sub-' stantial drying.

, 6. The method of producing milled soap from molten anhydrous soap which comprises bringing molten anhydrous soap into contact with a hydrating liquid in a mixing chamber in such proportions'that the moisture content of the mixture exceeds that desired for milling, substantially im- 'mediately subjecting the same to intense mechanically induced mixing, expelling the mixture from said mixing chamber, evaporating moisture in excess of that desired for milling whereby the soap is solidified, adding perfume, and milling and plodding the soap.

7. The method of hydrating molten anhydrous soap which comprises bringing molten anhydrous soap into contact with water-containing liquid in a mixing chamber, substantially immediately subjecting the same to intense mechanically induced mixing, expelling the mixture from said chamber into a mass of molten hydrated soap, withdrawing hydrated soap from said mass and reintroducing it into said mixing chamber as at least a portion of said water-containing liquid, and removing hydrated soap from said mass for further processing.

8. The method which comprises directing streams of molten anhydrous soap and hydrated soap into a chamber toward a rotating impeller, intimately mixing said streams by intense agitation induced said impeller, and discharging the mixture from said chamber by centrifugal force imparted by said impeller and with the aid of steam generated in said chamber.

9. An apparatus for hydrating molten anhydrous soap which comprises means adapted to contain a mass of hydrated soap, means for adding a stream of molten anhg drous soap to said mass of hydrated soap, means for withdrawing hydrated soap from one portion of said mass and returning it to another portion thereof, means for adding water to said hydrated soap, and means for removing hydrated soap from said mass for further processing.

MARTIN HILL ITI'NER.

REFEEEIICEE @ITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,123,647 Clayton July 12, 1938 2,126,099 Duncan Aug. 9, 1938 2,133,666 Mills Oct. 18, 1938 2,137,213 Clayton Nov. 15, 1938 2,142,982 Thurman Jan. 3, 1939 2,142,983 Thurman Jan. 3, 1939 2,185,653 Thurman Jan. 2, 1940 2,190,592 Clayton Feb. 13, 1940 2,190,615 Thurman Feb. 13, 1940 2,249,675 Thurman July 15, 1941 FOREIGN PATENTS Number Country Date 487,399 Great Britain June 16, 1938 

1. AN APPARATUS FOR PRODUCING SOAP OF A DESIRED MOISTURE CONTENT WHICH COMPRISES MEANS ADAPTED TO CONTAIN A SOAP MASS, MEANS FOR DISCHARGING A STREAM OF SOAP INTO SAID SOAP MASS THROUGH A PIPE WHOSE OUTLET IS SURROUNDED BY SAID SOAP MASS, MEANS FOR REMOVING VAPORS FROM SAID FIRST NAMED MEANS, MEANS FOR SUPPLYING WATER TO SAID FIRST NAMED MEANS, MEANS FOR WITHDRAWING MATERIAL FROM SAID SAAP MASS, AND MEANS FOR VAPORIZING WATER FROM THE MATERIAL THUS REMOVED TO PRODUCE A SOAP OF DESIRED MOISTURE CONTENT.
 2. THE METHOD OF PRODUCING A SOLID SOAP FROM MOLTEN ANHYDROUS SOAP WHICH COMPRISES BRINGING MOLTEN ANHYDROUS SOAP INTO CONTACT WITH WATERCONTAINING LIQUID IN A MIXING CHAMBER, SUBSTANTIALLY IMMEDIATELY SUBJECTING THE SAME TO INTENSE MECHANICALLY INDUCED MIXING, EXPELLING THE MIXTURE FROM SAID CHAMBER WITH THE AID OF STREAM GENERATED IN SAID CHAMBER, AND SOLIDIFYING THE EXPELLED SOAP. 